Secret to treating 'Achilles' heel' of perovskite alternatives to silicon solar panels revealed

A team of researchers from the UK and Japan have found that defects in the material are responsible for structural changes that lead to degradation.

The researchers used a combination of techniques to mimic the process of aging under sunlight and observe changes in the materials at the nanoscale, helping them gain new insights into the materials, which also show potential for optoelectronic applications such as energy efficient LEDs and X-ray detectors, but are limited in

Their results could accelerate the development of long- lasting, commercially available photovoltaics.

It is cheaper to process perovksites than it iscrystalline Silicon. They can be printed with liquid ink and produce a thin film of the material.

While the overall energy output of perovskite solar cells can often meet, in the case of multi-layer —tandem— devices, the limited longevity of the devices is a key barrier.

A typical solar panel, like the ones you see on the roof of a house, lasts about 20 years without significant performance losses.

Because of their lower production costs, perovskite devices may not need as long a lifetime as their Silicon counterparts to enter some markets. To realize widespread decarbonization, cells will need to operate for at least a decade. Researchers and manufacturers are still working on a device with the same stability.

Researchers at the University of Cambridge and the OIST in Japan have found a way to treat the Achilles heel of perovskites.

The team used a toolkit of high spatial-resolution techniques to observe the properties of these thin.

The team used similar techniques to shine light on the defects that cause deficiencies in the performance of perovskite photovoltaics.

The most interesting dynamics are occurring at the trap clusters, which are caused by the aging of solar cell devices, according to co-author Dr. Stuart Macpherson from Cambridge's Cavendish Laboratory.

We now know that the changes we see are related to the degradation of the films. As a result, efficiency-limiting carrier traps can now be linked to the equally crucial issue of solar cell longevity.

It suggests that if you can address the formation of these surface, it is pretty exciting.

The researchers have shown that it is possible to control how many detrimental phases form and how long the device will last by tuning the chemical composition and how the film forms.

The most stable devices seem to be serendipitously lowering the density of detrimental phases through subtle compositional and structural modifications.

The group is optimistic that their latest findings will bring us closer to the first commercially available photovoltaic devices.

The first production lines already producing modules are on the verge of commercialization, according to Dr. Sam Stranks from Cambridge's Department of Chemical Engineering and Biotechnology.

We now know that any leftover unwanted phases will be bad news for the longevity of the cells. The manufacturing processes need to incorporate careful tuning of the structure and composition across large area to eliminate any trace of these unwanted phases. This is a great example of fundamental science.

It has been very satisfying to see the approaches that we have developed at OIST and Cambridge over the past several years provide direct visuals of these tiny residual unwanted phases, and how they change over time.

There is no existing infrastructure for processing monocrystalline Silicon, which makes it possible for perovskite devices to be made in countries. Because they can be solution processed and printed so easily, you don't have to pay the initial cost. They offer a viable option for low- and middle-income countries to transition to solar energy.

More information: Samuel Stranks, Local Nanoscale Phase Impurities are Degradation Sites in Halide Perovskites, Nature (2022). DOI: 10.1038/s41586-022-04872-1. www.nature.com/articles/s41586-022-04872-1

Tiarnan A. S.Doherty et al, Stabilized tilted-octahedra halide perovskites, inhibit local formation of performance-limiting phases. There is a science.abl4890.

Journal information: Science , Nature Citation: Secret to treating 'Achilles' heel' of perovskite alternatives to silicon solar panels revealed (2022, May 24) retrieved 24 May 2022 from https://phys.org/news/2022-05-secret-achilles-heel-perovskite-alternatives.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.